That's a possibility. Though I'm not sure what's in plastic that could be missing in the diet. Mine have eaten dirt/clay to get the minerals. Can you get Steve's Raw Dog Food? It's sold mostly at Whole Foods Market. http://www.stevesrealfood.com/.
I'm picking up a new tri today from BRAT and I'm going to try it. The woman who runs BRAT said it help her B that had chronic diarrhea. You can mix it with kibble. I'm also going to use Organix dry dog food to mix it with.
Let us know how it goes.. and we would love for you to join us next weekend in Livermore for the BCONC lure trial/puppy match/club meeting….